Rosneft Chairman, Igor Sechin, has stepped down making BP’s proposed $18 billion (£11 billion) deal less likely.
Sechin, who is also Russia’s Deputy Prime Minister, resigned his position after President Medvedev ordered that ministers be removed from the boards of state companies.
BP’s merger with state-controlled Rosneft is already blocked by a court injunction.
A new Board of Directors is to be elected at the upcoming annual general meeting of shareholders.
Vladimir Bogdanov and independent directors Hans-Joerg Rudloff, Andrei Kostin and Aleksandr Nekipelov were nominated for consideration as interim Board Chairman.
It was decided by a majority of five votes to three that the duties of the Chairman of the Board would be temporarily assigned to Aleksandr Nekipelov.